From c439ef2e71f6c98aa0a9de1d2036a5422454171c Mon Sep 17 00:00:00 2001
From: Andrei Formiga <archimedes_siracusa@hotmail.com>
Date: Fri, 27 May 2016 19:03:15 -0300
Subject: [PATCH 1/2] Fix issue #4001: invalid pragma {. hint[]: off .}

The bug was in processNote, module pragmas. The code assumed that
a nkBracketExpr AST node always had two children (without testing
this), and tried to access elements with index 0 and 1 in the sons
array of the nkBracketExpr node.

The code that triggered the bug was just {. hint[]: off .}
by itself in a module; in this case the nkBracketExpr has only
one children in the sons array, so the code in processNote caused
an out-of-bounds array access.

This commit also adds a test to guarantee that this pragma is
rejected, as is.
---
 compiler/pragmas.nim       | 1 +
 tests/pragmas/thintoff.nim | 6 ++++++
 2 files changed, 7 insertions(+)
 create mode 100644 tests/pragmas/thintoff.nim

diff --git a/compiler/pragmas.nim b/compiler/pragmas.nim
index 38d17eb62a..dc09d8fc47 100644
--- a/compiler/pragmas.nim
+++ b/compiler/pragmas.nim
@@ -277,6 +277,7 @@ proc processDynLib(c: PContext, n: PNode, sym: PSym) =
 proc processNote(c: PContext, n: PNode) =
   if (n.kind == nkExprColonExpr) and (sonsLen(n) == 2) and
       (n.sons[0].kind == nkBracketExpr) and
+      (n.sons[0].sons.len == 2) and
       (n.sons[0].sons[1].kind == nkIdent) and
       (n.sons[0].sons[0].kind == nkIdent):
       #and (n.sons[1].kind == nkIdent):
diff --git a/tests/pragmas/thintoff.nim b/tests/pragmas/thintoff.nim
new file mode 100644
index 0000000000..7a5b344e66
--- /dev/null
+++ b/tests/pragmas/thintoff.nim
@@ -0,0 +1,6 @@
+# issue #4001
+discard """
+  errormsg: "invalid pragma: hint[]: off"
+"""
+
+{. hint[]: off .}

From 929865ff628322da213f2296b6dcef3f4107129f Mon Sep 17 00:00:00 2001
From: Andrei Formiga <archimedes_siracusa@hotmail.com>
Date: Fri, 27 May 2016 19:38:54 -0300
Subject: [PATCH 2/2] Deleted test for fix #4001

---
 tests/pragmas/thintoff.nim | 6 ------
 1 file changed, 6 deletions(-)
 delete mode 100644 tests/pragmas/thintoff.nim

diff --git a/tests/pragmas/thintoff.nim b/tests/pragmas/thintoff.nim
deleted file mode 100644
index 7a5b344e66..0000000000
--- a/tests/pragmas/thintoff.nim
+++ /dev/null
@@ -1,6 +0,0 @@
-# issue #4001
-discard """
-  errormsg: "invalid pragma: hint[]: off"
-"""
-
-{. hint[]: off .}